Another math teacher here at Scattergood asked me at dinner, “What about trigonometry on other shapes, like ellipses?” We know about hyperbolic cosines, but what about other things?
I whipped up this geogebra applet. There are 3 green points you can find and drag – make sure you play with all three, because they’re pretty cool!
Riley Lark, Created with GeoGebra
I didn’t go to the trouble to make this one interactive, but here’s a square cosine wave: